Modeling of catalytic partial oxidation and dry reforming of CH4 in fixed-bed reactors: Comparison of 3D particle-resolved (PRCFD) and 1D simulations

• Modeling of catalytic fixed-bed reactors with 3D particle-resolved and 1D simulations • Comparison of three beds with two chemistries (CPOX, DRM) for four Reynolds numbers. • Beds had tube to particle diameter ratios: 1.1/2/7 and particle counts: 23/86/6000. • Investigation of impact of various correlations for submodels in 1D approach. • Best choice of correlations for 1D model depends on bed geometry and reaction type. This work compares a detailed 3D particle-resolved CFD model and a 1D pseudo-continuum model for catalytic fixed-bed reactors for three different tube-to-particle diameter ratios (1.1/2/7) over a wide range of particle Reynolds numbers (29/145/290/1450). Dry reforming of methane and catalytic partial oxidation are simulated using microkinetics mechanisms in both frameworks. In the 1D model, over 100 combinations of literature correlations for heat and mass transfer and overall heat transfer coefficients are evaluated against 3D reference solutions. The study shows that no universal correlation set is valid. Instead, the best choice of correlations for the 1D model depends on bed geometry and reaction type. The results delineate conditions where simplified 1D models remain reliable and where fully resolved CFD becomes necessary for reactor design and analysis.